Extracellular substance from the white rot basidiomycete Irpex lacteus involved in wood degradation
H Tanaka, T Hirano, G Fuse, A Enoki
Cellulases, phenol oxidase, and a substance that both produced and reduced H2O2 were isolated from cultures containing wood or glucose on which the white-rot fungus Irpex lacteus was growing. The rate of wood degradation by the fungus with different amounts of glucose in the medium was measured. More of the substance that produced and reduced H2O2 was found extracellularly in cultures containing wood than in cultures containing glucose. The extent of one-electron oxidation activity of the extracellular substance was correlated with that of the wood-degrading activity, but the extent of phenol oxidase activity was not. The extracellular substance catalyzed the hydroxylation of phenol to hydroquinone and catechol in the presence of H2O2 or of NADH and O2. The substance seemed to be a glycopeptide containing Fe(II) and its molecular weight was very low.
Keywords: EXTRACELLULAR SUBSTANCE; GLYCOPEPTIDE; HYDROGEN PEROXIDE; FAGUS CRENATA; IRPEX LACTEUS; ONE ELECTRON OXIDATION; WHITE ROT